Network & IT Tools
Subnetting, CIDR, permissions and scheduling — the daily calculators of network and system administration, done with exact bit math in your browser. Your internal addressing plans, MAC addresses and cron schedules never touch a server, and everything works offline.
- IP Subnet Calculator Enter any IPv4 address with a prefix (/24) or mask (255.255.255.0) and get the network, broadcast, usable range and host count
- IPv6 Subnet Calculator Paste any IPv6 address with a prefix and get its canonical compressed form, full expanded form, the network range, and how many addresses and /64 subnets it contains.
- CIDR to IP Range Converter Turn 192.168.0.0/22 into its first–last address range, or turn an arbitrary range into the smallest set of CIDR blocks that covers it exactly.
- IP Address Converter Type an IP in any form
- IPv6 Expand / Compress Paste one IPv6 address or a whole list: get the fully expanded form for databases and sorting, or the canonical RFC 5952 compressed form for configs and docs.
- Chmod Calculator Tick read/write/execute for owner, group and others
- Cron Expression Parser Paste any 5-field cron expression
- MAC Address Formatter Paste a MAC in any format and get every standard notation
- Download Time Calculator Enter a file size and your connection speed to see how long the transfer takes
- Bandwidth Converter Enter a speed in any unit to convert it instantly between bit-rates (Mbps) and byte-rates (MB/s).
For the terminal and the wiring closet
Network and systems work runs on precise, unforgiving math: IPv4 and IPv6 subnetting (computed at exact 128-bit precision), CIDR ranges, chmod permission bits, cron expressions and MAC/EUI-64 addresses. A single wrong bit changes a whole subnet, so these tools give exact results and explain the breakdown — network, broadcast, usable hosts, wildcard mask and more.
Everything is computed locally in your browser, so internal addressing plans never leave your device, and the tools work offline on a locked-down machine. For hashes, encoders and other build-time helpers, see Developer Tools.
Frequently asked questions
Are the IPs and network plans I enter uploaded anywhere?
No. Every calculation — subnet math, CIDR conversion, cron parsing — runs in your browser. Internal addressing plans, MAC addresses and cron schedules are exactly the kind of infrastructure detail you should not paste into tools that log requests, which is why these don't have a server side at all.
Why use a subnet calculator instead of asking an AI chatbot?
Subnet math is bit-exact, and language models routinely get subnet boundaries, usable-host counts and CIDR splits subtly wrong — errors you only discover when the firewall rule doesn't match. These calculators do the actual binary arithmetic, so the answer is exact every time.
Do the tools cover IPv6?
Yes — there's a dedicated IPv6 subnet calculator with exact 128-bit math and an expand/compress normalizer implementing RFC 5952. With IPv6 now carrying the majority of traffic to major services, dual-stack fluency is the point.
Do they work offline?
Yes — once loaded, every tool runs without a connection, so they work in the server room where the Wi-Fi doesn't.